Chrysler New Yorker. Manual — part 41

The cooling system is designed around the coolant.

The coolant must accept heat from engine metal, in
the cylinder head area near the exhaust valves and
engine block. Then carry this heat to the radiator
where the tube/fin radiator can give it up to the air.

The use of aluminum cylinder blocks, cylinder

heads, and water pumps requires special corrosion
protection. Mopar

t Extended Life Coolant (orange in

color) or the equivalent ethylene glycol base coolant
with corrosion inhibitors (called OAT, for Organic
Additive Technology) is recommended for best engine
cooling without corrosion, when mixed only to a
freeze point of -37°C (-35°F) to -59°C (-50°F). If it
loses color or becomes contaminated, drain, flush,
and replace with fresh properly mixed solution.

WARNING:

ANTIFREEZE IS AN ETHYLENE GLY-

COL BASE COOLANT AND IS HARMFUL IF SWAL-
LOWED OR INHALED. IF SWALLOWED, DRINK
TWO GLASSES OF WATER AND INDUCE VOMIT-
ING. IF INHALED, MOVE TO FRESH AIR AREA.
SEEK MEDICAL ATTENTION IMMEDIATELY. DO NOT
STORE IN OPEN OR UNMARKED CONTAINERS.
WASH SKIN AND CLOTHING THOROUGHLY AFTER
COMING IN CONTACT WITH ETHYLENE GLYCOL.
KEEP OUT OF REACH OF CHILDREN. DISPOSE OF
GLYCOL BASE COOLANT PROPERLY, CONTACT
YOUR DEALER OR GOVERNMENT AGENCY FOR
LOCATION OF COLLECTION CENTER IN YOUR
AREA. DO NOT OPEN A COOLING SYSTEM WHEN
THE ENGINE IS AT OPERATING TEMPERATURE OR
HOT UNDER PRESSURE, PERSONAL INJURY CAN
RESULT. AVOID RADIATOR COOLING FAN WHEN
ENGINE COMPARTMENT RELATED SERVICE IS
PERFORMED, PERSONAL INJURY CAN RESULT.

RADIATOR

The radiators are cross-flow types (horizontal

tubes) with design features that provide greater
strength as well as sufficient heat transfer capabili-
ties to keep the engine satisfactorily cooled.

CAUTION:

Plastic tanks, while stronger than brass

are

subject

to

damage

by

impact,

such

as

wrenches, or heat from torch.

COOLANT PRESSURE BOTTLE CAP

The Coolant bottle is equipped with a pressure cap

which releases pressure at some point within a range
of 110 kPa

6 14 kPa (16 psi 6 2 psi) (Fig. 7).

The system will operate at higher than atmospheric

pressure which raises the coolant boiling point, thus
allowing increased radiator cooling capacity.

There is a spring-loaded vent valve in the center of

the cap that allows the system to pressurize and
depressurize without creating a vacuum. If the valve
is stuck open, coolant will escape to the overflow
hose. There is also a gasket in the cap to seal to the
top of the filler neck.

CAUTION: Use only the pressure cap specified for
this vehicle. Use of other pressure caps can lead to
coolant loss and overheating.

DUAL FAN MODULE

All models use electric motor driven fans. The fan

modules include a motor support and shroud. The
module is fastened to the radiator by screws with
square nuts and retaining clips (Fig. 8).

The dual fan module is a combination of 2 fans

mounted in a one piece shroud which operate at two
speeds and are simultaneously activated. The dual
fan system improves engine cooling and air condi-
tioning performance in hot weather and severe driv-
ing conditions, while reducing fan noise and power
consumption. Attempts to reduce high temperature
gauge reading by increasing engine speed, can
increase high temperature.

Fig. 7 Pressure Cap and Bottle

Fig. 8 Fan Module

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GENERAL INFORMATION (Continued)

FAN SHROUD

All vehicles have fan shrouds to improve fan air

flow efficiency. The shroud supports the electric fan
motor and fan.

AUTOMATIC TRANSMISSION OIL COOLER

The transmission oil cooler circuit consists of a

series connected internal cooler mounted inside the
left radiator tank and an auxiliary external oil cooler
mounted to the front of the air conditioning con-
denser (Fig. 9).

Steel tubes and rubber lines supply the oil from

the transmission to the internal oil cooler and return
the oil to the transmission from the auxiliary exter-
nal oil cooler.

Use only approved transmission oil cooler hoses.

Since these hoses are molded to fit space available,
molded hoses are required. The steel tubes must be
flared to ensure sealing of the hose. Torque oil cooler
hose clamps to 2.5 N·m (22 in. lbs.).

ENGINE OIL COOLER—3.2L

The 3.2L engine uses an engine oil cooler that is

mounted inside the right radiator tank. An oil cooler

pressure control valve is used to control pressure to
the cooler. Engine oil travels from the control valve
through the supply line and into the cooler. The
engine oil exits the cooler through the oil return line
and is returned to the engine oil pan (Fig. 10).

ENGINE BLOCK HEATER

On all models an engine block heater is available

as an optional accessory. The heater, operated by
ordinary house current (110 Volt A.C.) through a
power cord and connector behind the radiator grill.
This provides easier engine starting and faster
warm-up when the vehicle is operated in areas hav-
ing extremely low temperatures.

DESCRIPTION AND OPERATION

ENGINE THERMOSTAT

The engine cooling thermostats are wax pellet

driven, reverse poppet (3.2L), and dual poppet (2.7L)
types. The thermostats are located in the inlet side of
the engine to provide fast warm up and to optimize a
constant temperature in the engine. The thermostats

Fig. 9 Transmission Oil Cooler

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COOLING

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GENERAL INFORMATION (Continued)

are designed to prevent leakage through them and to
guarantee a minimum engine operating temperature
of 90°C (195°F). They also automatically reach wide
open at a temperature of approximately 102°C
(215°F) so they do not restrict flow to the radiator as
temperature of the coolant rises in hot weather to
around 104°C (220°F). Above102°C (215°F) the cool-
ant temperature is controlled by the radiator, fan,
and ambient temperature, not the thermostat.

COOLANT PERFORMANCE

Performance is measurable. For heat transfer, pure

water absorbs 1 btu for each degree of temperature
rise for each pound of water. This formula is altered
when necessary additives to control boiling, freezing,
and corrosion are added as follows:

• Pure Water (1 btu) boils at 100°C (212°F) and

freezes at 0°C (32°F).

• 100 Percent ethylene glycol (.7 btu) can cause an

engine to run hot, cause detonation, and will freeze
at -22°C (-8°F).

• 50/50 Ethylene Glycol and Distilled Water (.82

btu) is the recommended combination that provides a
freeze point of -37°C (-35°F). The radiator, water
pump, engine water jacket, radiator pressure cap,
thermostat, temperature gauge, coolant sensor and
heater are all designed for 50/50 ethylene glycol.

Where required, a 56 percent glycol and 44 percent

water mixture will provide a freeze point of -46°C
(-50°F).

NOTE: Richer mixtures cannot be measured with
field equipment and can lead to problems associ-
ated with 100 percent glycol. If there is doubt that
the coolant mixture is too rich for field equipment
to measure, put a sample in a clean container. Add
exactly the same amount of water and retest. If the
coolant in the vehicle is 100% antifreeze, the diluted
sample will read 50%. If the coolant in the vehicle
was 70% antifreeze and 30% water, the diluted sam-
ple will read as 35%, etc.

SELECTION AND ADDITIVES

The use of aluminum cylinder blocks, cylinder

heads, intake manifolds, and water pumps require
special corrosion protection. Mopar

t Extended Life

Coolant (orange in color) or the equivalent is recom-
mended for optimum engine cooling and protection
against corrosion when mixed to a freeze point of
-37°C (-35°F) to -59°C (-50°F). If it looses color or
becomes contaminated; drain, flush, and replace with
fresh properly mixed solution.

CAUTION: Do not use well water, or suspect water
supply in cooling system. A 50/50 ethylene glycol
and distilled water mix is recommended.

Fig. 10 Engine Oil Cooler—3.2L

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DESCRIPTION AND OPERATION (Continued)

RADIATOR HOSES AND CLAMPS

WARNING:

IF

VEHICLE

HAS

BEEN

RUN

RECENTLY, WAIT 15 MINUTES BEFORE WORKING
ON VEHICLE. RELIEVE PRESSURE BY PLACING A
SHOP TOWEL OVER THE CAP AND WITHOUT
PUSHING DOWN ROTATE IT COUNTERCLOCKWISE
TO THE FIRST STOP. ALLOW FLUIDS TO ESCAPE
THROUGH THE OVERFLOW TUBE AND WHEN THE
SYSTEM STOPS PUSHING OUT COOLANT AND
STEAM AND PRESSURE DROPS.

The hoses are removed by using constant tension

clamp pliers to compress hose clamp (Fig. 11).

A hardened, cracked, swollen, severely abraded, or

restricted hose should be replaced. Do not damage
radiator inlet and outlet when loosening hoses.

Radiator hoses should be routed without any kinks

and indexed as designed. The use of molded hoses is
required.

Spring type hose clamps are used in all applica-

tions. If replacement is necessary replace with the
original Mopar

t equipment spring type clamp.

CAUTION: Use of general purpose pliers can bend
the clamps to a out of round condition, Resulting in
a loss of clamping strength.

ENGINE BLOCK HEATER

The engine block heater is mounted in the cylinder

block, near the right rear corner. The block heater is
a cylinder type design which transfers heat through
the aluminum engine block without penetrating the
cooling system. The power cord must be secured
in its retainer clips, and not positioned so it
could contact linkages or exhaust manifolds
and become damaged.

WATER PUMP

The water pump body is made of aluminum with a

plastic swept vane impeller. The water pump is
bolted to the front of the timing cover, and driven by
the timing belt on the 3.2L engine. On the 2.7L
engine, the water pump attaches directly to the cyl-
inder block and is driven by the back side of the pri-
mary timing chain. The water pump is the heart of
the cooling system, pumping the coolant through the
engine block, cylinder head, heater core, and radia-
tor.

NOTE: The water pump on all models can be
replaced without discharging the air conditioning
system.

Fig. 11 Hose Clamp Tool

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COOLING

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DESCRIPTION AND OPERATION (Continued)